Last month, former South Carolina police officer Michael Slager pleaded guilty in federal court to violating Walter Scott's civil rights by shooting him with no justification.

Slager pulled over Scott in 2015, due to a broken taillight. Scott ran from the traffic stop. He was videotaped being shot five times in the back.

Slager’s case is unusual. First, he was prosecuted and second he was convicted.

“Most police shootings are found to be legally justified,” Philip M. Stinson, an associate professor of criminal justice at Bowling Green State University, told the New York Times.

“Under the relevant Supreme Court case law,” Stinson said, “if an officer has a reasonable apprehension of an imminent threat of serious bodily injury or deadly force being imposed against the officer or somebody else, then they’re justified in using deadly force.”

The Supreme Court case is Graham v. Connor. In 1989, the high court ruled the “use of force must be judged from the perspective of a reasonable officer on the scene, rather than with the 20/20 vision of hindsight.” The court gave deference to the police who are forced to make split-second decisions in “tense, uncertain and rapidly evolving” situations.

This week, jurors acquitted a black police officer of first-degree reckless homicide in the killing of a black Milwaukee man who threw away the gun he was carrying during a brief foot chase after a traffic stop.

In Cincinnati, a jury is scheduled to deliberate today for the fifth day in the second trial of Ray Tensing, a white former University of Cincinnati police officer charged with murder and voluntary manslaughter. He shot Sam DuBose, an unarmed black man, during a 2015 traffic stop. The first trial in November ended with a hung jury.

In most instances, a homicide conviction requires prosecutors to establish the suspect’s intent. When that suspect is a police officer, the issue of intent becomes murky. Police officers are often confronted in a flash with difficult life threatening decisions.

In Tensing’s trials, both sides called use-of-force experts and other witnesses to testify about police training, reported CBS News. The prosecution said Tensing could have de-escalated the situation and did not need to shoot. Defense witnesses said officers are trained to “stop the threat” if they believe they are in danger.

Tensing testified in both trials, “I didn’t shoot to kill him. I didn’t shoot to wound him. I shot to stop his actions.”

According to the Washington Post, 963 men and women were shot and killed by police in 2016. So far in 2017, the number is 460. Few of those officer-involved shootings result in arrest and only about one in five officers arrested are ever convicted.

Professor Stinson told The Associated Press, “Juries and judges seem reluctant to second-guess the split-second life or death decisions of police officers in violent street encounters in the course of their job ... and will give the benefit of every doubt to an officer on trial in these cases. That is not so for other types of crimes by police officers, but it certainly is the case in these shooting cases.”

While there is a recent surge in officers charged with murder or manslaughter for shooting suspects, it’s too early to tell if the upswing is the beginning of a trend. Stinson believes newer technology like cell phone video and police body cameras have produced a “tipping point,” leading the public to take a more critical view of the police’s version of events.

— Matthew T. Mangino is of counsel with Luxenberg, Garbett, Kelly & George P.C. His book “The Executioner’s Toll, 2010” was released by McFarland Publishing. You can reach him at www.mattmangino.com and follow him on Twitter at @MatthewTMangino.